Characteristics of reservoirs for inter-salt shale oil of Qianjiang Formation, Qianjiang Sag, Jianghan Basin: a case study of the Eq34-10 rhythm
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摘要: 江汉盆地始新统潜江组盐间页岩油是近年来研究的热点和难点。为了明确盐间页岩储层岩相及其储集物性,综合运用岩心观测、岩石薄片鉴定、X衍射、高压压汞和页岩孔渗等资料,对潜江凹陷潜江组盐间页岩油储层岩相发育特征及其对储集物性的影响进行了研究。该区盐间页岩油储层主要包括富碳纹层状泥质白云岩相、富碳纹层状云/灰质泥岩相和钙芒硝充填富碳纹层状云质泥岩相3种不同类型的岩相类型,前2种岩相的孔隙度明显高于后者。不同岩相孔径分布差异明显,富碳纹层状泥质白云岩相以孔径大于41 nm的孔隙为主,中值孔喉半径为219 nm;而富碳纹层状云/灰质泥岩相和钙芒硝充填富碳纹层状云质泥质相则以孔径小于41 nm的孔隙为主,中值孔喉半径为21 nm。富碳纹层状泥质白云岩相岩性均一,具有良好的储集空间和较大的孔喉结构,页岩储层中的含油性较高,为盐间页岩油储层中的优势岩相,是研究区最有利的页岩油勘探目标。Abstract: The inter-salt shale oil of the Eocene Qianjiang Formation in the Jianghan Basin is a hot and difficult research target in recent years. In order to clarify the lithofacies and physical properties of the inter-salt shale reservoirs, based on core observation, thin section observation, X-ray diffraction, high-pressure mercury intrusion and shale porosity and permeability analyses, a case study was carried out for the Qianjiang Formation in the Qianjiang Sag of Jianghan Basin. Results showed that there were three types of lithofacies, including carbonaceous laminar argillaceous dolomites, carbonaceous lamellar dolomitic/lime mudstones and carbonaceous lamellar dolomitic mudstones filled with glauberites. The porosities of the first two lithofacies were significantly higher than that of the latter. The pore size distribution of different lithofacies showed that the carbonaceous laminar argillaceous dolomites were dominated by pores with radius greater than 41 nm, and the median pore-throat radius was 219 nm, while the other two facies were dominated by pores with pore radius less than 41 nm and the median pore-throat radius was 21 nm. The carbonaceous laminar argillaceous dolomites were indicated to be homogeneous in lithology. As reservoir, they have good reservoir space, larger pore-throat structure and higher oil content, and was the dominant facies in the inter-salt shale oil reservoir and is promising to be the most favorable shale oil exploration target in the study area.
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图 4 江汉盆地潜江凹陷潜江组盐间页岩岩心扫描照片
图版上部为白光照片,下部为荧光照片。a.纹层状泥晶白云岩(2 813.7~2 816.2 m),纹层状灰质/云质泥岩(2 816.2~2 819.3 m);b.纹层状灰质/云质泥岩(2 819.3~2 820.43 m),含钙芒硝条带纹层状云质泥岩(2 820.43~2 823.78 m)
Figure 4. White light and fluorescence scanning photos of inter-salt shales in Qianjiang Formatiom, Qianjiang Sag, Jianghan Basin
表 1 江汉盆地潜江凹陷潜江组潜34-10韵律盐间页岩层矿物成分统计
Table 1. Mineral composition of inter-salt shales in Eq34-10 rhythm, Qianjiang Formation, Qianjiang Sag, Jianghan Basin
% 井号 黏土矿物 硬石膏 石英 钾长石 斜长石 方解石 白云石 菱铁矿 黄铁矿 石盐 钙芒硝 BX7 $ \frac{0.6 \sim 39.1}{20.7 /(72)}$ $\frac{0.3 \sim 17.1}{1.3 /(72)} $ $ \frac{3.8 \sim 15.6}{8.2 /(72)} $ $\frac{0.5 \sim 4.4}{1.1 /(72)} $ $\frac{1.6 \sim 7.1}{4.3 /(72)} $ $ \frac{2.7 \sim 50.8}{22.6 /(72)}$ $\frac{12.1 \sim 73.8}{31.8 /(72)} $ $ \frac{0.1 \sim 13.1}{0.6 /(72)}$ $\frac{1.9 \sim 12.6(72)}{7.1 /(72)} $ $ \frac{0.1 \sim 0.3}{0.2 /(72)}$ $ \frac{0.4 \sim 5.8}{2.2 /(72)}$ BYY1 $ \frac{0.1 \sim 33.3}{12.2 /(117)}$ $ \frac{0.4 \sim 41.2}{3.4 /(117)}$ $ \frac{0.1 \sim 15}{7.3 /(117)}$ $ \frac{0.2 \sim 10.6}{0.7 /(117)}$ $\frac{1.9 \sim 20}{6.7 /(117)} $ $ \frac{0.3 \sim 65.1}{10.9 /(117)}$ $\frac{2.0 \sim 70.3}{28.7 /(117)} $ $ \frac{0.0}{(117)}$ $\frac{1.0 \sim 28.2}{4.3(117)} $ $ \frac{0.6 \sim 92}{3.7(117)}$ $\frac{1.4 \sim 91.3}{18.5(117)} $ BYY2 $ \frac{1.5 \sim 42.3}{12.4 /(128)}$ $ \frac{0.1 \sim 0.6}{0.2 /(128)}$ $\frac{1.9 \sim 16.4}{6.7 /(128)} $ $\frac{0.2 \sim 9}{0.5 /(128)} $ $\frac{2.7 \sim 15.5}{7.1 /(128)} $ $ \frac{1.0-45.0}{9.8 /(128)}$ $ \frac{3.7 \sim 74.3}{30.9 /(128)}$ $\frac{0.0}{(128)} $ $\frac{1.1 \sim 32.8}{5.4(128)} $ $\frac{0.6 \sim 63.2}{3.0(128)} $ $ \frac{3.0 \sim 84.1}{23.4(127)}$ W99 $\frac{5.7 \sim 54.7}{26.7 /(54)} $ $\frac{0.0}{(57)} $ $\frac{2.6 \sim 17.6}{10.8 /(57)} $ $\frac{0.1 \sim 2.2}{0.3 /(57)} $ $\frac{0.2 \sim 5.6}{1.8 /(57)} $ $ \frac{1.5 \sim 39.8}{9.7 /(57)}$ $ \frac{2.8 \sim 76.9}{23.6 /(57)}$ $\frac{0.0}{(57)} $ $ \frac{1.5 \sim 9.3}{3.2(57)}$ $\frac{0.8 \sim 6.3}{1.5(57)} $ $\frac{3.6 \sim 82.5}{22.3(57)} $ 平均 16.0 1.4 7.8 0.7 5.7 12.6 29.3 0.1 5.1 2.5 17.6 注:表中数据意义为$\frac{ { 最小值 \sim 最大值 }}{\text { 平均值(样品数) }} $。 表 2 江汉盆地潜江凹陷潜江组潜34-10韵律盐间页岩储集物性数据
Table 2. Reservoir properties of inter-salt shales in Eq34-10 rhythm, Qianjiang Formation, Qianjiang Sag, Jianghan Basin
井号 孔隙度/% 渗透率/10-3 μm2 BX7 1.9~9.1/6.0(18) 0.06~1.6/0.55(18) BYY1HF 4.1~10.2/8.5(65) 0.13~3.6/1.5(40) BYY2 5.1~18/11.9(78) 0.23~5.1/2.18(47) W99 14.2~31.3/22.(4) 0.7~1.3/1.0(2) 注:表中数据意义为:最小值~最大值/平均值(样品数)。 -
[1] ZOU Caineng, YANG Zhi, CUI Jingwei, et al. Formation mechanism, geological characteristics and development strategy of nonmarine shale oil in China[J]. Petroleum Exploration and Development, 2013, 40(1): 15-27. doi: 10.1016/S1876-3804(13)60002-6 [2] 杨智, 侯连华, 陶士振, 等. 致密油与页岩油形成条件与"甜点区"评价[J]. 石油勘探与开发, 2015, 42(5): 555-565. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201505002.htmYANG Zhi, HOU Lianhua, TAO Shizhen, et al. Formation conditions and "sweet spot" evaluation of tight oil and shale oil[J]. Petro-leum Exploration and Development, 2015, 42(5): 555-565. https://www.cnki.com.cn/Article/CJFDTOTAL-SKYK201505002.htm [3] 白静. 我国页岩油资源勘探潜力巨大[N]. 中国矿业报, 2019-11-12(5).BAI Jing. Oil shale resources in China has large prospecting potentia[N]. China Mining Magazine, 2019-11-12(5). [4] 邹才能, 杨智, 朱如凯, 等. 中国非常规油气勘探开发与理论技术进展[J]. 地质学报, 2015, 89(6): 979-1007. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201506001.htmZOU Caineng, YANG Zhi, ZHU Rukai, et al. Progress in China's unconventional oil & gas exploration and development and theore-tical technologies[J]. Acta Geologica Sinica, 2015, 89(6): 979-1007. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201506001.htm [5] 金之钧, 胡宗全, 高波, 等. 川东南地区五峰组-龙马溪组页岩气富集与高产控制因素[J]. 地学前缘, 2016, 23(1): 1-10. https://www.cnki.com.cn/Article/CJFDTOTAL-DXQY201601002.htmJIN Zhijun, HU Zongquan, GAO Bo, et al. Controlling factors on the enrichment and high productivity of shale gas in the Wufeng-Longmaxi Formations, southeastern Sichuan Basin[J]. Earth Science Frontiers, 2016, 23(1): 1-10. https://www.cnki.com.cn/Article/CJFDTOTAL-DXQY201601002.htm [6] ZHAO Xianzheng, ZHOU Lihong, PU Xiugang, et al. Exploration breakthroughs and geological characteristics of continental shale oil: a case study of the Kongdian Formation in the Cangdong Sag, China[J]. Marine and Petroleum Geology, 2019, 102: 544-556. doi: 10.1016/j.marpetgeo.2018.12.020 [7] YANG Zhi, ZOU Caineng, WU Songtao, et al. Formation, distribution and resource potential of the "sweet areas (sections)" of continental shale oil in China[J]. Marine and Petroleum Geology, 2019, 102: 48-60. doi: 10.1016/j.marpetgeo.2018.11.049 [8] LI Wenhao, LU Shuangfang, XUE Haitao, et al. Oil content in argillaceous dolomite from the Jianghan Basin, China: Application of new grading evaluation criteria to study shale oil potential[J]. Fuel, 2015, 143: 424-429. doi: 10.1016/j.fuel.2014.11.080 [9] 王芙蓉, 何生, 郑有恒, 等. 江汉盆地潜江凹陷潜江组盐间页岩油储层矿物组成与脆性特征研究[J]. 石油实验地质, 2016, 38(2): 211-218. doi: 10.11781/sysydz201602211WANG Furong, HE Sheng, ZHENG Youheng, et al. Mineral composition and brittleness characteristics of the inter-salt shale oil reservoirs in the Qianjiang Formation, Qianjiang Sag[J]. Petroleum Geology & Experiment, 2016, 38(2): 211-218. doi: 10.11781/sysydz201602211 [10] HOU Yuguang, WANG Furong, HE Sheng, et al. Properties and shale oil potential of saline lacustrine shales in the Qianjiang Depression, Jianghan Basin, China[J]. Marine and Petroleum Geology, 2017, 86: 1173-1190. doi: 10.1016/j.marpetgeo.2017.07.008 [11] 李乐, 王自翔, 郑有恒, 等. 江汉盆地潜江凹陷潜三段盐韵律层页岩油富集机理[J]. 地球科学, 2019, 44(3): 1012-1023. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX201903028.htmLI Le, WANG Zixiang, ZHENG Youheng, et al. Mechanism of shale oil enrichment from the salt cyclotherm in Qian3 member of Qianjiang Sag, Jianghan Basin[J]. Editorial Committee of Earth Science-Journal of China University of Geosciences, 2019, 44(3): 1012-1023. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX201903028.htm [12] 徐二社, 陶国亮, 李志明, 等. 江汉盆地潜江凹陷盐间页岩油储层不同岩相微观储集特征: 以古近系潜江组三段4亚段10韵律为例[J]. 石油实验地质, 2020, 42(2): 193-201. doi: 10.11781/sysydz202002193XU Ershe, TAO Guoliang, LI Zhiming, et al. Microscopic reservoir characteristics of different lithofacies from inter-salt shale oil reservoir in Qianjiang Sag, Jianghan Basin: a case study of Paleogene Eq34-10 rhythm[J]. Petroleum Geology & Experiment, 2020, 42(2): 193-201. doi: 10.11781/sysydz202002193 [13] 郑有恒. 江汉盆地潜江凹陷潜江组岩性油藏勘探方向及对策[J]. 石油实验地质, 2010, 32(4): 330-336. doi: 10.11781/sysydz201004330ZHENG Youheng. Exploration direction and strategy for lithologic accumulations in Qianjiang Formation of the Qianjiang Sag, Jianghan Basin[J]. Petroleum Geology & Experiment, 2010, 32(4): 330-336. doi: 10.11781/sysydz201004330 [14] 张永生, 杨玉卿, 漆智先, 等. 江汉盆地潜江凹陷古近系潜江组含盐岩系沉积特征与沉积环境[J]. 古地理学报, 2003, 5(1): 29-35. https://www.cnki.com.cn/Article/CJFDTOTAL-GDLX200301002.htmZHANG Yongsheng, YANG Yuqing, QI Zhixian, et al. Sedimentary characteristics and environments of the salt-bearing series of Qianjiang formation of the paleogene in Qianjiang Sag of Jianghan Basin[J]. Journal of Palaeogeography, 2003, 5(1): 29-35. https://www.cnki.com.cn/Article/CJFDTOTAL-GDLX200301002.htm [15] 方志雄. 潜江盐湖盆地盐间沉积的石油地质特征[J]. 沉积学报, 2002, 20(4): 608-613. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200204011.htmFANG Zhixiong. Hydrocarbon exploration signification of intersalt sediments in Qianjiang Saline Lake Basin[J]. Acta Sedi-mentologica Sinica, 2002, 20(4): 608-613. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB200204011.htm [16] 陈树杰, 赵薇. 江汉盆地潜江凹陷盐间泥质白云岩油藏储层物性特征探讨[J]. 长江大学学报(自然科学版), 2010, 7(1): 168-170. https://www.cnki.com.cn/Article/CJFDTOTAL-CJDL201001053.htmCHEN Shujie, ZHAO Wei. Study on physical properties of inter-salt argillaceous dolomite reservoirs in Qianjiang Sag of Jianghan Basin[J]. Journal of Yangtze University (Natural Science Edition), 2010, 7(1): 168-170. https://www.cnki.com.cn/Article/CJFDTOTAL-CJDL201001053.htm [17] 熊智勇, 吴世强, 王洋, 等. 江汉盐湖盆地盐间泥质白云岩油藏地质特征与实践[J]. 地质科技情报, 2015, 34(2): 181-187. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201502027.htmXIONG Zhiyong, WU Shiqiang, WANG Yang, et al. Geological characteristics and practice for intersalt argillaceous dolomites reservoir in the Qianjiang Depression of Jianghan Salt Lake Basin[J]. Geological Science and Technology Information, 2015, 34(2): 181-187. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ201502027.htm [18] 江继纲. 潜江凹陷潜江组油源的探讨[J]. 石油学报, 1985, 6(2): 23-29. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB198502005.htmJIANG Jigang. About the source of oil in the Qianjiang formation[J]. Acta Petrolei Sinica, 1985, 6(2): 23-29. https://www.cnki.com.cn/Article/CJFDTOTAL-SYXB198502005.htm [19] CARROLL A R, BOHACS K M. Lake-type controls on petroleum source rock potential in nonmarine basins[J]. AAPG Bulletin, 2001, 85(6): 1033-1053. [20] BAO Jianping, ZHU Cuishan, MA Anlai. The relationship between methylated chromans and maturity of organic matter in the source rocks from Jianghan hypersaline basin[J]. Science in China Series D: Earth Sciences, 2009, 52(S1): 34-41. [21] 孙中良, 王芙蓉, 何生, 等. 潜江凹陷古近系盐间典型韵律层页岩孔隙结构[J]. 深圳大学学报(理工版), 2019, 36(3): 289-297. https://www.cnki.com.cn/Article/CJFDTOTAL-SZDL201903010.htmSUN Zhongliang, WANG Furong, HE Sheng, et al. The pore structures of the shale about typical inter-salt rhythm in the Paleogene of Qianjiang depression[J]. Journal of Shenzhen University(Science & Engineering), 2019, 36(3): 289-297. https://www.cnki.com.cn/Article/CJFDTOTAL-SZDL201903010.htm [22] 胡莹, 卢双舫, 李文浩, 等. 江汉盆地新沟嘴组泥质白云岩含油性分析[J]. 东北石油大学学报, 2015, 39(3): 76-82. https://www.cnki.com.cn/Article/CJFDTOTAL-DQSY201503011.htmHU Ying, LU Shuangfang, LI Wenhao, et al. Analysis of oil-bearing property of argillaceous dolostone in Xingouzui formation, Jianghan basin[J]. Journal of Northeast Petroleum University, 2015, 39(3): 76-82. https://www.cnki.com.cn/Article/CJFDTOTAL-DQSY201503011.htm [23] 龙玉梅, 陈曼霏, 陈风玲, 等. 潜江凹陷潜江组盐间页岩油储层发育特征及影响因素[J]. 油气地质与采收率, 2019, 26(1): 59-64. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201901006.htmLONG Yumei, CHEN Manfei, CHEN Fengling, et al. Characteristics and influencing factors of inter-salt shale oil reservoirs in Qianjiang Formation, Qianjiang Sag[J]. Petroleum Geology and Recovery Efficiency, 2019, 26(1): 59-64. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201901006.htm [24] 陶国亮, 刘鹏, 钱门辉, 等. 潜江凹陷潜江组盐间页岩含油性及其勘探意义[J]. 中国矿业大学学报, 2019, 48(6): 1256-1265. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201906011.htmTAO Guoliang, LIU Peng, QIAN Menhui, et al. Oil-bearing characte-ristics and exploration significance of inter-salt shale in Qianjiang formation, Qianjiang depression, Jianghan basin[J]. Journal of China University of Mining & Technology, 2019, 48(6): 1256-1265. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGKD201906011.htm -